Munakata et al., Chem. Abs. 86:55073 g (1977) have recited preparing bis(octaidenyl) 1,2-cyclohexanedicarboxylates by reaction between active hydrogen-containing compounds or carboxylic acid anhydrides and 1,3-dienes, in the presence of Pd compounds and phosphines. The resulting reaction mixtures are treated with peroxides and then with hydrogen and/or carbon monoxide to reduce palladium compounds and remove palladium.
Collin et al., Chem. Abs. 96:122005 h, have recited reacting an alpha-olefin, tert-butyl hydroperoxide and carbon monoxide, in the presence of a palladium-phosphine mixture, to produce products of both oxidation and reduction. The mechanism is said to include decomposition of an alkyl-palladium sigma bond by the hydroperoxide.
The interaction of peroxides with organic compounds of Group V elements has been reviewed by Swern, ed., "Organic Peroxides," Krieger Publishing Co., vol. 3 (1981), pages 236-238. Various peroxides are reported to react with R.sub.3 P to produce corresponding phosphine oxides. See also, Goodyear, Jr., Chem. Abs. 54:16381 g.
Horner et al., "Die Reduktion organischer Peroxyde mit tertiaren Phosphinen" Annalen, vol. 591 (1955), pages 138-152, consider reduction products from reaction between tertiary phosphines and various organic peroxides.
Vinylically-unsaturated organosilicon compounds are useful as adhesion promoters, particularly for electronic applications. Formulators of adhesives for electronic utilization generally require vinylically-unsaturated organosilicon compounds, containing very low levels of impurities, particularly heavy metal and other inorganic impurities. Organosilicon compounds frequently contain heavy metals, halogens, alkali metals and phosphorus. Any of these materials, in amounts greater than about 1-10 ppm, can cause objectionable properties in adhesive formulations, containing vinylically-unsaturated organosilicon compounds.
The Heck vinylation reaction has been used to vinylate various kinds of compounds, including vinylically-unsaturated organosilicon compounds. The preparation of polysiloxane-bridged bisbenzocyclobutene monomers has been recited by Gros, U.S. Pat. No. 4,759,874, and Schrock, U.S. Pat. No. 4,812,588, both herein incorporated by reference. Schrock '588 discloses chromatography of a product from 4-bromobenzocyclobutene and 1,1'-divinyltetramethyldisiloxane over silica gel. Other silane-containing compounds have been synthesized by Hahn et al., U.S. Pat. No. 4,831,172, herein incorporated by reference. Kirchhoff et al., U.S. Pat. No. 4,724,260, herein incorporated by reference, have prepared an acetylenically-unsaturated organosilicon compounds from 4-bromobenzocyclobutene and trimethyl silylacetylene, using bistriphenylphosphine palladium (II) chloride and cuprous iodide catalysts and triethylamine as hydrogen halide acceptor.
The palladium-catalyzed vinylation of organic halides has been reviewed by Heck, Organic Reactions, vol. 27 (1982), beginning at page 345. Process conditions, recited at page 360, do not require the use of a solvent, although an organic amine can apparently function as a solvent. Other solvents used heretofore include acetonitrile, methanol, dimethylformamide, N-methylpyrrolidinone and hexamethyl phosphoramide.
Heck, U.S. Pat. No. 3,922,299, incorporated herein by reference, teaches that the reaction can be carried out with or without a solvent. Suggested solvents include acetonitrile, tetrahydrofuran or excess olefin.
It is therefore the object of this invention to provide an improved process for purification of vinylically-unsaturated organosilicon compounds to produce materials with very low levels of inorganic impurities, which are suitable for electronic applications.